The use of radiography, urodynamic studies and cystoscopy in the evaluation of voiding dysfunction

Children with dysfunctional voiding disorder often undergo radiological, cystoscopic or urodynamic evaluation to identify an anatomical or organic cause. We determined the role of these studies in the evaluation, management and ultimate outcome of a large patient population with voiding dysfunction at a single institution.

We retrospectively evaluated the records of 1, 153 children with dysfunctional voiding disorder treated from 1990 to 1999. A thorough history and physical examination with specific emphasis on voiding patterns were done and urinalysis was performed in all cases. Ultrasound of the urinary system and excretory urography were done in 1,050 (91%) and 24 (2%) patients, respectively, while voiding cystourethrography was performed in 672 (58%), including 564 with a history of nonfebrile urinary tract infection. Cystoscopy and a formal urodynamic study were performed in 61 (5%) and 40 (3.5%) cases, respectively.

Mean patient age at referral was 6 years (range 3 to 14). Of the children 74% were girls and 26% were boys. Physical examination of the abdomen, back, genitalia and neurological system was unremarkable in all cases. Ultrasound of the upper urinary system was normal in 1,018 patients (97%) and showed insignificant pyelectasis in 32 (3%). All 24 excretory urography studies were normal and voiding cystourethrography was normal in 470 of 672 cases (70%). Unilateral and bilateral low grade, and unilateral high grade reflux was present in 108, 19 and 3 patients, respectively. Urodynamic studies were performed in 40 children who did not respond to standard treatment. We noted detrusor instability in 16 patients, detrusor-sphincter dyssynergia in 6 and sensory abnormality in 3, while the study was completely normal in 10. Cystoscopy revealed normal findings in 17 cases, trabeculations in 21, inflammation in 20 and type 1 posterior urethral valves in 2.

The incidence of upper tract changes and positive anatomical findings in children with voiding dysfunction is too low to justify routine radiological evaluation and cystoscopy. However, in those who present with a nonfebrile urinary tract infection there remains an important role for voiding cystourethrography. We do not recommend routine urodynamics in children with voiding disorder because this study does not change therapy or influence the final outcome. Thorough history and physical examination lead to the correct diagnosis and treatment in the majority of children. A focus on correcting faulty voiding behavior with the judicious administration of antibiotics and anticholinergic therapy leads to a favorable outcome in most cases.